Sensor devices and energy emitting devices are well known tools, used for example in aircraft or missiles for detecting, tracking and/or homing onto a target. Such devices often include electro-optical sensors, radar and the like.
There are many known applications where different types of sensors are used with airborne platforms, and the sensors are commonly configured for simultaneous operation through a common aperture. In some such systems having a plurality of electro-optical sensors, some including laser radar or other optical elements, a system of mirrors or other optical components may be used for enabling each of the sensors to look through the common aperture at the same time, or at alternating periods via a movable mirror arrangement, for example. Applications are also known having separate dedicated sensors, including a radar system and an electro-optical sensor for example, in which a different part of the available aperture is assigned to each of the sensors. In yet other applications, each sensor may be configured and mounted to an aircraft, for example, as a separate and independent sensor system.
By way of general background, the following patents provide examples of sensor systems.
U.S. Pat. No. 6,262,800 is directed to a method and apparatus for guiding a weapon to a target using an optical seeker having dual semi-active laser (SAL) and laser radar (LADAR) modes of operation. The seeker further includes a high speed sighting mirror for switching between modes to guide the weapon to the target.
U.S. Pat. No. 6,193,188 discloses a missile including a fuselage with a roll axis and a nod axis perpendicular to the roll axis, and a conformal window mounted to a forward-facing end of the fuselage. There is a sensor system with a field of regard through the window and a line of sight, and a sensor system pointing mechanism affixed to the airframe and upon which the sensor system is supported. A linear translational mechanism is operable to translate the sensor system away from the window with increasing angular deviation of the line of sight of the sensor system from the roll axis.
U.S. Pat. No. 5,134,409 relates to a surveillance sensor provided with at least one surveillance radar antenna and at least one co-located and co-rotating electro-optical surveillance sensor mechanically connected to said radar antenna. A combined panoramic picture is compiled by combining information from both sensors using a common track unit.
U.S. Pat. No. 7,136,726 discloses an airborne reconnaissance system comprising: gimbals having at least two degrees of freedom; at least one array of light sensors positioned on the gimbals, for being directed by the same within at least two degrees of freedom; map storage means for storing at least one Digital Elevation Map of an area of interest, divided into portions; Inertial Navigation System for real-time providing to a gimbals control unit navigation and orientation data of the aircraft with respect to a predefined global axes system; portion selection unit for selecting, one at a time, another area portion from the area of interest; and servo means for directing the gimbals. The system uses data from the inertial navigation system and from the digital elevation map for real-time calculating direction to selected area portions, and for maintaining the direction during integration of light from the terrain, and for producing corresponding images of area portions.
U.S. Pat. No. 6,484,619 discloses an observation or aiming system for a self-propelled vehicle, and includes a post pivoting about a bearing axis relative to the vehicle. The post carries a body for an optical block and a thermal camera which are mounted to pivot about an elevation axis perpendicular to the bearing axis. The system also includes a radar channel having a radar transmitter unit mounted on the body, a radar detection unit mounted on the body close to the bearing axis and concentration means situated in the body for concentrating radar waves on the radar detection unit. The optical block, the thermal camera, and the radar channel are secured so as to always have the same orientation in elevation and in bearing, and thus the same observation direction
U.S. Pat. No. 5,796,474 and U.S. Pat. No. 6,057,915 disclose a projectile tracking system for acquiring and precisely tracking a projectile in flight in order to reveal the source from which the projectile was fired. A telescope focuses infrared light from a relatively large field of view on to an infrared focal plane array. In a projectile detection mode, the system searches for the infrared signature of the fast moving projectile. The telescope's field of view is steered in the azimuth by a step and stare mirror, and when a projectile is detected the system switches to a tracking mode and the mirror is steered to track the projectile. A short pulse high repetition rate laser in a laser radar system provides a pulsed laser beam which is optically coaligned with the telescope axis. Mirror angular position information, laser radar pulse travel time and the missile spot position on detector array are used by a computer to calculate bullet trajectory information and to determine the source or origin of the projectile using known ballistic trajectory methods.